THE LINEARIZED EQUATIONS OF MOTION UNDERLYING THE DYNAMIC STABILITY OF AIRCRAFT, SPINNING PROJECTILES, AND SYMMETRICAL MISSILES

摘要

Linearized equations of motion are derived for both conventional aircraft having mirror symmetry and spinning projectiles or missiles having rotational and mirror symmetry. The aerodynamic coefficients are introduced as a formal series expansion in the customary variables, with additional terms being included to account for the aerodynamic effects of spin. The requirements of symmetry are used to reduce the system of aerodynamic coefficients and, in the projectile or missile case, to clarify markedly the geometry. A common mathematical approach and standard NACA nomenclature are used throughout.nThe equations for aircraft are compared with those for missiles and shortcomings in the currently accepted theories are pointed out. The dynamic-stability requirements for spin-stabilized projectiles fire dis-cussed briefly.nThe results are applied to the analysis of flight-test data from the aerodynamics range. Relations are derived between the aerodynamic coeffi-cients and the constants of the equations of motion. A comparison is made with ballistic theory in current use and is found to be-satisfactory.